1. Field of the Invention
The present invention relates to image retrieval from an image database using keywords.
2. Description of the Related Art
In image retrieval from an image database, the necessity of higher efficiency increases as the number of image data in the database increases. A general procedure of image retrieval comprises: specifying some of the keywords, which have previously been given to the respective images, and retrieving an image having the specified keywords.
In some cases, a user cannot clearly recognize the user's own desire nor input any specific keyword for retrieval of a desired image, but has only ambiguous requirements to the image to be retrieved. In a conventional procedure applied for such cases, the user successively checks displayed images to find an image that meets the ambiguous requirements.
In these cases, however, it is difficult to extract an image that meets the user's vague requirements from the image database and display it with a high efficiency. The retrieval is accordingly very time-consuming.